The specific aims of the Neuropathology Core are to establish accurate, comprehensive neuropathological diagnoses using strict, reliable diagnostic criteria and to precisely document the neuropathological findings on brains of participants enrolled in the Patient/Control Registry, brain donors from the Framingham Heart Study and other brains referred for neuropathological examination.. These intensive neuropathological analyses, including quantitative histological, anatomical and immunocytochemical evaluations, facilitate clinicopathological, correlative studies of the functional, behavioral, and neuropsychiatric aspects of AD. In addition, the Boston University Brain Bank of the Neuropathology Core serves as a source of fresh, fixed and protocol has been established to ensure high quality fresh, fixed and frozen tissue to investigators requiring tissue with brief post-mortem intervals. The computerized database, maintained under the direction of the Administrative Core contains all clinical and pathological diagnoses, neuropathological data, post-mortem intervals, associated chronic diseases and storage conditions of the tissue. Tissue availability and distribution is monitored using a computer program specifically developed for this project. Quality assurance in tissue procurement, handling, processing storage and neuropathological diagnoses is provided by monthly meetings of the 5-member Neuropathology board. Tissue prioritization and distribution is also supervised by the Neuropathology board. The autopsy rate on participants enrolled in Patient Control Registry currently averages 76%. A continued effort will be made to obtain brain donations from other Boston community participants, especially African Americans using educational approaches focused on care providers, especially medical students, senior housing staff and residents and participants families, in conjunction with the Education Core. As a further aim, the Neuropathology Core will provide well- characterized blood-brain barrier endothelial cells obtained from post- mortem donors, for researchers who wish to carry out AD-related studies on cultured living cells.